1. Field of Invention
This invention relates to the field of medical devices. More specifically, this invention relates to a system for delivery of gas products to a patient and monitoring of gas products exhaled by the patient.
2. Background
Epidural steroid injections, sacroiliac joint injections, facet joint blocks, and radio frequency ablations are but a few of the wide range of medical procedures being used to help alleviate neck, back, and other joint pain and discomfort. In many of these medical procedures, patients are required to lie face down in a prone position so that a needle can be inserted into the patient's spine. Since the patient is lying face down, a pillow-type support is often used to support the patient's head during the procedure. Some pain is typically associated with the procedures given their invasive nature. Therefore, a patient will often need to be sedated or anesthetized to manage the patient's exposure to such pain. Oxygen delivery and continuous patient monitoring is requisite in the sedated or anesthetized patient. Therefore, in addition to providing comfortable support for the patient's head, the pillow-type support must also provide for unobstructed breathing and patient monitoring.
Current oxygen delivery systems include, but are not limited to, nasal cannulas, face masks, Laryngeal Mask Airways (LMA), and endotracheal tubes (ETT). Selection of the oxygen delivery system is based on the level of sedation, patient position and other individual patient parameters. For the patient in the prone position undergoing a general anesthetic, the standard of care is an endotracheal tube. However, for the prone patient not under general anesthesia, the current oxygen delivery systems all have significant limitations. For example, the ETT or LMA would not be comfortably tolerated by the sedated patient and would therefore not provide an appropriate airway. The nasal cannula and face masks would require that plastic tubing be in contact with the patient's face, thus creating pressure points against the patient's skin and his or her pillow, probably leading to irritation, abrasions, and general discomfort. Still further, not all of these systems allow for monitoring of the patient's expired, end-tidal carbon dioxide (CO2), which is paramount in determining the appropriate safe dose of the sedating medications. Consequently, an end-tidal CO2 siphoning hose must be added to the system to safely monitor the patient. Such hoses are often another source of pressure points against the patient's face.
Another issue that must be taken into consideration is the positioning and support of the prone patient's head and neck. Currently there exists no pillow or headrest specifically designed for the awake, prone patient. A standard pillow is usually employed with the patient's head turned to the side. This position creates uncomfortable pressure points against one side of the patient's face, as well as an unnatural position of the patient's neck. If a face mask is used, there is also a risk that the edge of the mask may migrate into the patient's eyes and cause a corneal abrasion.
Therefore, what is needed is a system for providing an oxygen enriched environment without the need to attach tubing to the patient which can be irritating and cause pressure points.